CAMEA: Simulations and Kinematic Calculations

During the design of CAMEA extensive simulations and cinematic calculations were performed to explore the waste parameter space. These have led to a far better understanding of the instrument performance as well as new ideas to improve the instrument. Many simulations of the backend were done using a simpler triple axis model of the instrument but the final performance simulations were done using the full proposed ESS instrument

CAMEA: Comparison to the Colder Chopper Spectrometer

The Cold chopper and CAMEA spectrometers are in many ways equivalent. One uses several incoming energies combined with a continuous outgoing energy band while the other use a continuous incoming band and several outgoing energies, and both have big angular coverage. They do however also have some key differences. CAMEA have a higher flux in each channel while the cold chopper have a bigger angular coverage, bigger resolution flexibility, and more freedom in choosing its energy range. Since CAMEA cannot compete with the cold chopper at very high resolutions it is important to investigate how the CAMEA compares to the cold chopper in the primary operational region of CAMEA. For this comparison we have thus concentrated on settings where CAMEA excels (1.4% energy resolution, in plane scattering). We choose to consider only cold samples i.e. where down scattering is dominating and a wavelength band of 3.1 \AA to 4.76 \AA

CAMEA: Technical Solutions

CAMEA is a new instrument concept so it is possible that the construction could or maintenance of the instrument would be hampered by technical details. In order to prevent this a technical predesign have been performed. This is not a final technical solution with bolts and nuts but a 3d drawing where the important elements were put into place to confirm that it could be constructed in reality and that it would be possible to get access to the key areas for maintenance. Further the design has been used as a basis for the cost estimate. Since the primary instrument will not be unique the design has concentrated on the secondary instrument

Spectroscopic database for TROPOMI/Sentinel-5P: CO and H2O at 2.3μm

The TROPOspheric Monitoring Instrument (TROPOMI) aboard the European Space Agency's Copernicus Sentinel-5 Precursor satellite, to be launched this year, mandates high-accuracy spectral reference data for CO and H2O in the 2.3μm region [1]. We present measurements of absorption line parameters for H2O and for the 2-0 rovibrational band of CO to be used in TROPOMI atmospheric retrievals. The experiments were carried out on a Bruker IFS 125HR Fourier transform spectrometer and a multispectrum fitting software developed at DLR was used for parameter retrieval [2] using the Hartmann-Tran-Profile [3,4]. In the case of carbon monoxide, we report line intensities, air-broadening and -shift parameters for lines of the 2-0 rovibrational band, which serve as a useful validation of the HITRAN2012 spectral database [5] while our analysis of Dicke narrowing, speed dependence and Rosenkranz line mixing emphasizes the importance of modern line shape functions. Comparisons with previous studies of these non-Voigt parameters (e.g. [6]) show good agreement. As for H2O, spectral parameters were measured in the 4190cm-1-4340cm-1 spectral range. Comparisons of measured line intensities of the ν3 band show remarkable agreement (<1.5% deviation on average) with ab initio values [7,8] and we will present air-broadening, -narrowing and -shift parameters together with their temperature dependences. References [1] J.P. Veefkind et al, Remote Sensing of Environment 120, 70 (2012) [2] J. Loos et al, 13th HITRAN database conference, 2014 (doi: 10.5281/zenodo.11156) [3] N.H. Ngo et al, JQSRT 129, 89 (2013) [4] N.H. Ngo et al, JQSRT 134, 105 (2014) [5] L.S. Rothman et al, JQSRT 130, 4 (2013) [6] V.M. Devi et al, JQSRT 113, 1013 (2012) [7] L. Lodi et al, J Chem Phys 135, 034113 (2011) [8] J. Tennyson, University College London, Private communicatio

Sünde ist also nichts anderes als Ungehorsam - Widerstand und Wandel bei Spinoza

Die vorliegende Untersuchung widmet sich dem konservativ erscheinendem Widerstandverbot innerhalb der politischen Philosophie Baruch Spinozas. Dabei wird im Widerstandsverbot ein subversives Moment ausgemacht, welches den Wandel als die Grundlage des Staates und seinen Strukturen zeigt. In der Folge wird dargestellt, dass Spinoza den Widerstand und den Wandel in einer sehr spezifischen Weise denkt: Er richtet sich gegen die Gefahr, die von einer Regierung ausgeht, die gegen die eigenen Grundlagen der Souveränität handelt. Auf diese Weise tragen gehorsame Bürger*innen, wenn sei den Grundlagen der Souveränität gegenüber Gehorsam sind, zum Wandel bei, beziehungsweise ermöglichen diesen.This study is dedicated to the seemingly conservative prohibition of resistance within the political theory of Baruch Spinoza. Within the said prohibition of resistance, a subversive moment is identified, which shows change as the basis of the state and its structures. Subsequently, it is shown that Spinoza thinks resistance and change in a very specific way: they are directed against the danger posed by a government that acts against its own foundations of sovereignty. In this way, obedient citizens, if obedient to the foundations of sovereignty, contribute to, or enable, change

CAMEA: Guide Report

This document describes the best current candidate for a CAMEA guide made by the optimizer guide bot. The guide bot tool generates the McStas instrument and iFit files necessary for guide optimization, making it easy to investigate a large number of possibilities. The baseline requirements for the CAMEA guide is a 15 mm x 15 mm sample 0.6 m from the end of the guide, with a divergence requirement of ±0.75 degrees in the horizontal direction and ±1.0 degrees in the vertical direction. The distance between moderator and sample is 170 m. The guide does provide flux in a larger area than the requirement and at larger divergences, but the phase space illumination is only uniform within the requirement. The guide is intended to be used for the wavelength range 1.65 \AA to 6.4 \AA, but was optimized for a wavelength range of 1.0 \AA to 3.6 \AA, because experience with the optimizer shows that the results are better when optimizing for a slightly lower wavelength range than needed

A Prismatic Analyser concept for Neutron Spectrometers

A development in modern neutron spectroscopy is to avoid the need of large samples. We demonstrate how small samples together with the right choice of analyser and detector components makes distance collimation an important concept in crystal analyser spectrometers. We further show that this opens new possibilities where neutrons with different energies are reflected by the same analyser but counted in different detectors, thus improving both energy resolution and total count rate compared to conventional spectrometers. The technique can be combined with advanced focusing geometries and with multiplexing instrument designs. We present a combination of simulations and data with 3 energies from one analyser. The data was taken on a prototype installed at PSI, Switzerland, and shows excellent agreement with the predictions. Typical improvements will be 2 times finer resolution and a factor 1.9 in flux gain compared to a Rowland geometry or 3 times finer resolution and a factor 3.2 in flux gain compared to a single flat analyser slab

Multi-Q mesoscale magnetism in CeAuSb2_2

We report the discovery of a field driven transition from a striped to woven Spin Density Wave (SDW) in the tetragonal heavy fermion compound CeAuSb$_2$. Polarized along $\bf c$, the sinusoidal SDW amplitude is 1.8(2) $\mu_B$/Ce for $T \ll T_N$=6.25(10) K with wavevector ${\bf q}_{1}=( \eta, \eta, \frac{1}{2} )$ ($\eta=0.136(2)$). For ${\bf H}\parallel{\bf c}$, harmonics appearing at $2{\bf q}_{1}$ evidence a striped magnetic texture below $\mu_\circ H_{c1}=2.78(1)$ T. Above $H_{c1}$, these are replaced by woven harmonics at ${\bf q}_{1}+{\bf q}_2=(2\eta, 0, 0)+{\bf c}^*$ until $\mu_\circ H_{c2}=5.42(5)$ T, where satellites vanish and magnetization non-linearly approaches saturation at 1.64(2) $\mu_B$/Ce for $\mu_\circ H\approx 7$ T.Comment: 5 pages, 4 figure

The Reference System in the Model of PGE: Proposing a Generalized Description of Reference Products and their Interrelations

Samsung recently introduced a new smartphone display with increased breaking resistance, which will probably be relevant for future cars as well. This example shows that subsystems, in general artefacts from former development processes can be relevant for subsequent projects. Their integration has to be planned, i.a. even before the original product is in the market and across branches. The research on supporting methods requires a suitable description model for this phenomenon. Research in design reuse and PGE – product generation engineering addresses this only partially yet. Design reuse focuses on the informational aspect, PGE refers primarily to reference products. This contribution aims at closing this gap as a basis for future research. Two case studies from industry projects by the authors and an example from foresight and product planning show the role of artefacts from former development processes in running projects. It is described which artefacts are used as a reference, why they are used and when. Based on these findings the authors propose the term “reference system” to depict the whole set of artefacts, which serves as a basis for every product development project